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 ###Instrução: Qual é o número médio de vice-campeonatos que a Universidade Nacional, que possui mais de 2 campeonatos no total, tem?
 ###Tabelas: CREATE TABLE ukraine_managers (ukraine_managers_id AUTO_INCREMENT PRIMARY KEY, Manager VARCHAR, Ukraine career VARCHAR, Played INT, Drawn INT, Lost INT, Win % INT) CREATE TABLE other_appearances (other_appearances_id AUTO_INCREMENT PRIMARY KEY, Year INT, Song VARCHAR, Album appearance VARCHAR, Album artist VARCHAR, Notes VARCHAR) CREATE TABLE number_of_championships_by_school (number_of_championships_by_school_id AUTO_INCREMENT PRIMARY KEY, University VARCHAR, Men's INT, Women's INT, Runner-up INT, Total Championships INT) CREATE TABLE 2_lyga_zone_north (2_lyga_zone_north_id AUTO_INCREMENT PRIMARY KEY, Position INT, Club VARCHAR, Games played INT, Wins INT, Draws INT, Loses INT, Goals scored INT, Goals conceded INT, Points INT) CREATE TABLE olympians (olympians_id AUTO_INCREMENT PRIMARY KEY, Last VARCHAR, First VARCHAR, Year INT, Sport VARCHAR, Country VARCHAR)  
SELECT AVG Runner-up FROM number_of_championships_by_school WHERE University = national university AND Total Championships > 2